Function sample_pcurves_to_polygon 

pub fn sample_pcurves_to_polygon<'a>(
    pcurves: impl IntoIterator<Item = &'a Curve2>,
    n: usize,
) -> GeopResult<Vec<Vector2>>

Sample pcurves, a loop’s in order, into a closed (u, v) polygon: n points evenly along each one’s domain, its end left out, as the next one starts there.